Laser rangefinder is an instrument that uses laser to accurately measure the policy interval. The laser rangefinder emits a very thin beam of laser rangefinder light to the policy during operation. The photoelectric element receives the laser beam reflected by the policy. The timer measures the time from the laser beam emission to reception and calculates the interval from the observer to the policy. If the laser is continuously launched, the measuring range can reach about 40 kilometers, and the fluorine lined butterfly valve can operate day and night. If the laser beam pulse, the general accuracy is certainly low, but for long distance, can achieve better relative accuracy. Hughes Aircraft scientist John Maiman developed the world's first laser in 1960.
On this basis, the military laser equipment is discussed on the basis of the United States. In 1961, the first military laser rangefinder passed the United States military certification experiment, laser rangefinder soon entered the useful consortium. Laser rangefinder is light in weight, small in size, simple in operation, fast in speed and accurate. Its error is only a fifth to a few hundredths of other optical rangefinders, so it is widely used in topographic survey, battlefield survey, tank survey, aircraft survey, ship survey, artillery survey, cloud survey, aircraft survey, missile survey and artificial satellite survey. It is an important technical equipment to improve the accuracy of tanks, aircraft, ships and artillery. As the price of laser rangefinder continues to decrease, laser rangefinder gradually began to be used in industry. A number of new micro rangefinders with fast ranging, small size, reliable function and other advantages have appeared at home and abroad, which can be widely used in industrial measurement and control, mines, ports and other fields. One-dimensional laser rangefinder is mainly used for interval measurement and positioning. ScanninglaserRangefinder (ScanninglaserRangefinder) is used to summarize measurement, positioning, regional monitoring and other fields. Three dimensional laser range Finder (3DLaserRangefinder) is used in three dimensional summary measurement, three dimensional spatial positioning and other fields.
1. Must the plane of the measured object be straight with the light?
General precision ranging needs to be matched with a total reflection prism, house measurement rangefinder directly with lubricating wall reflection measurement, mainly because the interval is relatively close, the signal strength of light reflection is large enough. You know, it has to be straight, otherwise the signal back is too weak to get an accurate interval.
2. What is the principle of infrared ranging or laser ranging?
The ranging principle can be attributed to the time required to measure the light round-trip policy and then calculate the interval D by the speed of light c=299792458m/s and the atmospheric refraction coefficient n. Because it is difficult to measure time directly, it is generally used to measure the phase of continuous wave, which is called phase-measuring rangefinder. There are also pulse rangefinders, typically the WILDDI-3000. Instead of measuring the phase of the infrared or laser, the phase of the signal modulated on the infrared or laser is measured. The construction industry has a handheld laser rangefinder for house measurements that works the same way.
3. Is it OK if the plane of the measured object is diffuse?
In general, thin plastic sheets can be used to deal with serious problems of diffuse reflection.